Proteïna FNR : un pas endavant en la investigació antimicrobiana

Al laboratori de Genètica Molecular Bacteriana, de l'Institut de Biotecnologia i de Biomedicina de la UAB, han estudiat quins són els mecanismes de regulació genètica que han permès que alguns bacteris, fins el dia d'avui, puguin desenvolupar-se en ambients anòxics. Sembla que la resposta està en la proteïna FNR, la qual, en cas de manca d'oxigen, s'encarrega d'activar l'enzim anaeròbic (una ribonucleotidil reductasa), essencial per al manteniment de la viabilitat cel·lular. Aquesta observació pot ser clau per al futur control farmacològic del creixement bacterià durant processos infecciosos

3D human motion sequences synchronization using dense matching algorithm

Annual Symposium of the German Association for Pattern Recognition (DAGM), 2006, Berlin (Germany)This work solves the problem of synchronizing pre-recorded human motion sequences, which show different speeds and accelerations, by using a novel dense matching algorithm. The approach is based on the dynamic programming principle that allows finding an optimal solution very fast. Additionally, an optimal sequence is automatically selected from the input data set to be a time scale pattern for all other sequences. The synchronized motion sequences are used to learn a model of human motion for action recognition and full-body tracking purposes.This work was supported by the project 'Integration of robust perception, learning, and navigation systems in mobile robotics' (J-0929).Peer Reviewe

The Acinetobacter baumannii Oxymoron: Commensal Hospital Dweller Turned Pan-Drug-Resistant Menace

During the past few decades Acinetobacter baumannii has evolved from being a commensal dweller of health-care facilities to constitute one of the most annoying pathogens responsible for hospitalary outbreaks and it is currently considered one of the most important nosocomial pathogens. In a prevalence study of infections in intensive care units conducted among 75 countries of the five continents, this microorganism was found to be the fifth most common pathogen. Two main features contribute to the success of A. baumannii: (i) A. baumannii exhibits an outstanding ability to accumulate a great variety of resistance mechanisms acquired by different mechanisms, either mutations or acquisition of genetic elements such as plasmids, integrons, transposons, or resistant islands, making this microorganism multi- or pan-drug-resistant and (ii) The ability to survive in the environment during prolonged periods of time which, combined with its innate resistance to desiccation and disinfectants, makes A. baumannii almost impossible to eradicate from the clinical setting. In addition, its ability to produce biofilm greatly contributes to both persistence and resistance. In this review, the pathogenesis of the infections caused by this microorganism as well as the molecular bases of antibacterial resistance and clinical aspects such as treatment and potential future therapeutic strategies are discussed in depth

Fumarate and nitrate reduction (FNR) dependent activation of the Escherichia coli anaerobic ribonucleotide reductase nrdDG promoter

The nrdDG promoter regulates transcriptional expression of the anaerobic ribonucleotide reductase of Escherichia coli, an essential enzyme required to supply the building blocks for DNA synthesis. In this work, binding of the pleiotropic FNR (fumarate and nitrate reduction) transcriptional regulator to the nrdDG promoter region and the effects of binding on transcription were investigated. Gel retardation analysis with purified FNR* demonstrated FNR interaction at two FNR sites, termed FNR-2 and FNR-1, while studies with altered FNR boxes indicated that the upstream FNR-2 site was essential for anaerobic activation of the nrdDG promoter. Although the FNR-1 site was not absolutely required, it allowed maximal expression of this promoter. These results suggest that the two sites have an additive effect in coordinating nrdDG expression in response to shifting oxygen concentrations. [Int Microbiol 2008; 11(1):49-56

Automatic learning of 3D pose variability in walking performances for gait analysis

This paper proposes an action specific model which automatically learns the variability of 3D human postures observed in a set of training sequences. First, a Dynamic Programing synchronization algorithm is presented in order to establish a mapping between postures from different walking cycles, so the whole training set can be synchronized to a common time pattern. Then, the model is trained using the public CMU motion capture dataset for the walking action, and a mean walking performance is automatically learnt. Additionally statistics about the observed variability of the postures and motion direction are also computed at each time step. As a result, in this work we have extended a similar action model successfully used for tracking, by providing facilities for gait analysis and gait recognition applications.Peer ReviewedPreprin

Hierarchical eyelid and face tracking

Most applications on Human Computer Interaction (HCI) require to extract the movements of user faces, while avoiding high memory and time expenses. Moreover, HCI systems usually use low-cost cameras, while current face tracking techniques strongly depend on the image resolution. In this paper, we tackle the problem of eyelid tracking by using Appearance-Based Models, thus achieving accurate estimations of the movements of the eyelids, while avoiding cues, which require high-resolution faces, such as edge detectors or colour information. Consequently, we can track the fast and spontaneous movements of the eyelids, a very hard task due to the small resolution of the eye regions. Subsequently, we combine the results of eyelid tracking with the estimations of other facial features, such as the eyebrows and the lips. As a result, a hierarchical tracking framework is obtained: we demonstrate that combining two appearance-based trackers allows to get accurate estimates for the eyelid, eyebrows, lips and also the 3D head pose by using low-cost video cameras and in real-time. Therefore, our approach is shown suitable to be used for further facial-expression analysis.Peer Reviewe

Numerical analysis and safety design of grounding systems in underground compact substations

Financiado para publicación en acceso aberto: Universidade da Coruña/CISUG[Abstract:] This paper presents a mathematical and numerical formulation to design and analyze grounding systems in underground electrical substations. The developed approach is based on the well known Maxwell’s Equations. The proposed problem is solved by means of the Boundary Element Method (BEM). The utilization of BEM allows to introduce the geometry and electrical characteristics of the enclosure in a uniform soil. Therefore, a more realistic approximation of the soil structure is achieved. This formulation allows to obtain the main parameters of these protection systems (the grid resistance, the Ground Potential Rise, and the step and mesh voltage). It also allows to compute the surface and step voltage distributions. In addition, as a secondary result, the voltage and current density distributions over the enclosure are obtained. Finally, two grounding system analyses of real underground electrical substations are presented to demonstrate the industrial application and the modelization capabilities of the proposed formulation.Xunta de Galicia; GRC2014/039Xunta de Galicia; ED431C2018/41Ministerio de Economía y Competitividad; DPI2015-68431RMinisterio de Ciencia, Innovación y Universidades; RTI2018-093366-B-I0

Fumarate and nitrate reduction (FNR) dependent activation of the Escherichia coli anaerobic ribonucleotide reductase nrdDG promoter

The nrdDG promoter regulates transcriptional expression of the anaerobic ribonucleotide reductase of Escherichia coli, an essential enzyme required to supply the building blocks for DNA synthesis. In this work, binding of the pleiotropic FNR (fumarate and nitrate reduction) transcriptional regulator to the nrdDG promoter region and the effects of binding on transcription were investigated. Gel retardation analysis with purified FNR* demonstrated FNR interaction at two FNR sites, termed FNR-2 and FNR-1, while studies with altered FNR boxes indicated that the upstream FNR-2 site was essential for anaerobic activation of the nrdDG promoter. Although the FNR-1 site was not absolutely required, it allowed maximal expression of this promoter. These results suggest that the two sites have an additive effect in coordinating nrdDG expression in response to shifting oxygen concentrations

Finestres al cel

We present an astronomy educational project intended for 16-year-old high school students that has been successfully deployed for 7 years under the Youth and Science Program of the Catalunya La Pedrera Foundation. The Youth and Science Program aims to encourage talented students to pursue careers in science and technology and a future as researchers. It consists of a two-week crash course covering all major topics in astronomy: stellar evolution, black holes, galaxy formation and evolution, cosmology, simulations, and gravitational waves, among many others. The classes focus on the relevant concepts in each of the aforementioned fields but without a detailed description of the math formalism or the most advanced concepts in modern physics, this to develop the students’ intuition and interest in the wonders of the Universe without overwhelming them. Theoretical sessions are complemented with a set of practical sessions that help students to consolidate the concepts. All theory and practical sessions in this project are being compiled in an outreach book addressed not only to the students of this project but also to the entire amateur astronomy community

Posture constraints for bayesian human motion tracking

Abstract. One of the most used techniques for full-body human tracking consists of estimating the probability of the parameters of a human body model over time by means of a particle filter. However, given the high-dimensionality of the models to be tracked, the number of required particles to properly populate the space of solutions makes the problem computationally very expensive. To overcome this, we present an efficient scheme which makes use of an action-specific model of human postures to guide the prediction step of the particle filter, so only feasible human postures are considered. As a result, the prediction step of this modelbased tracking approach samples from a first order motion model only those postures which are accepted by our action-specific model. In this manner, particles are propagated to locations in the search space with most a posteriori information avoiding particle wastage. We show that this scheme improves the efficiency and accuracy of the overall tracking approach